Oklahoma House Speaker Lance Cargill was delinquent in paying property taxes on his Harrah law office six years in a row, an investigation by The Oklahoman revealed. "I take full responsibility for this error,” the Republican leader said Friday in a statement prepared after flying to Florida for a meeting of the National Conference of State Legislatures. "I certainly apologize to the people of Oklahoma and to my colleagues, and will take steps to ensure these matters are handled in a timely and efficient manner in the future,” Cargill said. Oklahoma County Treasurer Butch Freeman said, "He's one of my favorite taxpayers because we make a lot of money on him in interest and penalty.” Cargill has faced widespread criticism over the last week for other tax problems. The Oklahoman reported Cargill failed to file his 2005 and 2006 personal income tax returns until getting a Jan. 7 warning from the state Tax Commission. Cargill blamed a miscommunication with an accountant. Cargill, who is an attor-ney, fell behind months on many of the property tax bills on his law office, county records show. His company, Harrah Professional Partnership, bought the office in September 2001. The property tax on the first year was paid on time but payments have been late every year since, records show. Local school districts are the biggest losers when Oklahoma property owners fail to pay their real estate taxes on time. More than half of the real estate taxes on Cargill's law office were designated for support of Harrah schools, records show. Smaller amounts go to support other schools in the county, the city of Harrah, Oklahoma County government, the library system, the Oklahoma City-County Health Department and a Choctaw technology center. Most of the original tax bills on the law office have been about $700 or less for the year. Cargill was supposed to pay at least half by Dec. 31 each year. He or his company has had to pay a total of $562.44 in penalties, interest and fees by paying the taxes late. None of the late fees go to the schools. The property taxes on Cargill's home are handled by a mortgage company and have been paid on time, the treasurer said. In his statement, Cargill said, "Unlike my home, my business property taxes are not automatically paid because the business is owned outright and there is no mortgage.” Cargill sent in a $1,623.93 check — dated Jan. 10 — to pay his overdue 2007 and 2006 property taxes on his law office, records show. The 2006 tax was more than a year overdue. The 2007 tax, at that point, was just days overdue. The check was not enough to cover both years, because of interest on the 2006 bill, and Cargill will be notified he must pay more, the treasurer said. Cargill's $752.66 property tax bill for 2007 will be considered delinquent until a full payment comes in, Freeman said. Cargill was eight months late in paying his 2005 property tax on the law office, the records show. The $811.12 check covered the tax, penalty and interest. Harrah Professional Partnership was more than seven months late in paying the 2004 property tax on the law office. The check was for $731.15. Cargill paid the 2003 property tax on the law office more than seven months late. The check was for $780.52. Harrah Professional Partnership also was more than seven months late in paying the 2002 property tax on the law office. The check was for $775.65. The treasurer said Cargill apparently took care of the late payments most years after getting delinquent tax notices. Those notices are mailed in July. Only 3.12 percent of property owners had failed to pay their 2006 real estate taxes as of June 30, the treasurer said.