Government revenuers have long suffered abuse at the hands of U.S. taxpayers. But they generally get the last laugh, ridding our wallets of due taxes.

They have faced a tougher task, however, in collecting sales taxes on purchases made on the Internet and from other out-of-state vendors. It’s not that they haven’t tried.

For years, Maine has asked income tax filers to pay a “use” tax, or sales tax, on these items. It’s collected with the state income tax, listed for 2003 on line 31 of the long form and line 27 of the short form. It is called a use tax because the items are used in Maine.

Some items are easily taxed, perhaps the most conspicuous being an automobile. If purchased out of state, it must be registered in Maine and the tax is collected by municipalities when the vehicle is registered. The 5 percent tax must be paid separately on items costing more than $5,000. Forms are available on the Internet and from some town offices.

But on less expensive items, it gets murkier. And tax officials fear they are losing huge amounts of potential revenue as Internet sales soar. The National Governors Association estimates that state and local governments are losing $35 billion a year to Internet sales. All but five states, New Hampshire being one, now collect a sales tax.

California and New York recently added a use-tax line to their state income tax forms, making a total of 20 states now attempting to collect the tax in that manner. But it’s not easy.

Just ask Elmer Pelletier. He is a deputy director of Maine’s Special Tax Division and his easy, friendly manner belies his revenuer status.

Pelletier said Maine sends a representative to meetings of state tax collectors where members try to figure out a way to make it possible to tax Internet and catalog sales when they are made. But it’s a Herculean undertaking, considering that the sales taxes vary from a 2 or 3 percent to 5 or 6 percent. And the items it applies to vary from state to state.

The federal government has shown no interest in taxing the Internet in any manner, preferring to let it become an economic growth engine, making buying easy for consumers and providing an accessible national flea market for sellers, from stores to auctions sites.

In Maine, businesses are required to keep a record of out-of-state purchases and pay the tax. But individuals are legally required to pay the tax but not required to keep records of their Internet purchases.

Hmmm.

Pelletier admits there’s an ambiguity here.

The solution the state prefers is for tax filers to use the handy table provided with the tax forms that figures the tax at 0.04 percent of adjusted gross income. Most Maine families would pay in the vicinity of $20. That would represent the tax on purchases of $400. Items costing more than $1,000 are treated separately and added to the amount derived from the table.

But how would the state know if you were cheating if you paid nothing or some lesser amount? They wouldn’t, of course, unless you were audited and then you would have to show why you paid the amount you did, although you hadn’t been legally required to keep such records.

Sounds like a good case for a court appeal. But what court would hear such a case, dealing in such a pittance? It’s clearly safer to use the table.

Who knows what will happen as Internet sales will likely continue to grow by leaps and bounds.

Hard to tell, but I’m not betting against the revenuers. Their track record is good.