19 C.F.R. § 4.92
No vessel other than a vessel documented for the coastwise trade, or which would be entitled to be so documented except for its tonnage (see § 4.80 ), may tow a vessel other than a vessel in distress between points in the U.S. embraced within the coastwise laws, or for any part of such towing (46 U.S.C. 55111 ) . The penalties for violation of this provision occurring on or before November 2, 2015, are a fine of from $350 to $1,100 against the owner or master of the towing vessel and a further penalty against the towing vessel of $60 per ton of the towed vessel. The penalties for violation of this section occurring after November 2, 2015, are a fine of from $1,096 to $3,446 against the owner or master of the towing vessel and a further penalty against the towing vessel of $187 per ton of the towed vessel (46 U.S.C. 55111 , as adjusted by the Federal Civil Penalties Inflation Adjustment Act Improvements Act of 2015).
19 C.F.R. §4.92