Allision vs. Collision: What’s the Difference?

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Just like motor vehicles have rules of the road, boats have rules of the water. There are state and federal laws that control maritime activity on U.S. waterways. The purpose of these laws is to prevent accidents and create uniform traffic control for commercial and recreational vessels.

Despite these laws, thousands of accidents occur each year on the navigable waters of the United States.

Maritime accidents can be classified into two categories – allision and collision. There are important legal differences between the two types of accidents. These differences may be key to determining fault and liability.

The Houston maritime injury lawyers at Haun Mena explain the differences between allision and collision and what you need to know about claiming injury compensation.

What’s the Difference Between Allision and Collision?

An allision is a boat accident where a moving vessel strikes a stationary object. A collision is a boat accident where two moving vessels strike each other.

The difference between the two is whether there are two moving objects at the time of impact or one object is moving and one is stationary.

The Difference Between Allision and Collision – Why Does it Matter?

The difference between allision and collision matters because there are differences in how liability is determined for an accident. When allision occurs, there is a presumption that the moving vessel is at fault. In a collision, there is a presumption against any party that violates a statute or regulation intending to prevent collisions.

Allisions and the Oregon Rule

The Oregon Rule is a presumption of fault that applies to allisions. When a moving vessel strikes a stationary vessel or object, the moving vessel is presumed to be at fault. The plaintiff must show that the object was visible or otherwise known.

The defendant may rebut the presumption by showing that they used reasonable care or by showing that the plaintiff was at fault. They may also show that the accident was simply unavoidable. The Oregon, 158 U.S. 186 (1895); Texas Eastern Transmission Corp. v. Tug Captain Dann, 898 F. Supp. 198 (S.D.N.Y. 1995).

Collisions and the Pennsylvania Rule

In a collision, there is no stationary object, so the Oregon Rule doesn’t apply. However, the Pennsylvania Rule applies. The Pennsylvania Rule says that if a party violates a statute that exists to prevent collisions, it’s presumed that they’re at fault for a collision.

There must be a law or regulation that applies. The injury suffered must be the kind that the law was intended to prevent. Generally, collisions on U.S. waterways are evaluated with a negligence standard, including comparative negligence, applying presumptions created by the Pennsylvania Rule. See The Pennsylvania, 86 U.S. 125 (1874).

The Pennsylvania Rule applies to allisions and collisions. The Oregon Rule applies only to allisions.

Drifting Vessels and the Louisiana Rule

The Louisiana Rule creates a presumption of fault when a drifting vessel hits a stationary object. The assumption is that the drifting vessel must have been mishandled or moored improperly.

The defendant may rebut the presumption with an affirmative showing that the drifting was an inevitable accident. To be a viable defense, the accident must not have been preventable with human skill and precaution. Pioneer Natural Resources U.S.A., Inc. v. Diamond Offshore Co., 638 F. Supp. 2d 665, 689 (E.D. La. 2009).

Rivers and Harbors Act of 1899

Negligence may not be the only standard that applies to evaluate accidents upon navigable waters in the United States. For example, the Rivers and Harbors Act of 1899 creates strict liability for actions impairing the usefulness of structures under the control of the United States for preserving or improving navigable waters. See United States v. Republic Marine, Inc., 627 F. Supp. 1425 (C.D. Ill. 1986).

Suits in Admiralty Act

46 U.S. Code § 30903 of the Suits in Admiralty Act waives government immunity for suits against vessels owned by the United States. Remedies provided by the Act are exclusive.

Determining applicable law

Remember, there are many federal and state laws that apply to maritime accidents and related litigation. Even in United States courts, choice of law analysis may result in the application of the 1910 Brussels Collision Convention (1910 Collision Convention) even though the United States is not a signatory. When the Convention is used, U.S. substantive law does not apply, including the Pennsylvania Rule.

Talk to a Maritime Accident Lawyer in Houston

Be sure to discuss the specifics of your case with an experienced maritime injury attorney, including presumptions of fault and applicable law. We invite you to talk to our maritime injury law firm in Houston about an allision or collision case and learn how we can help. Contact us today.

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