Allen Stanford, the Texan financier, knight of Antigua, Washington power player and billionaire benefactor of English cricket, has been found guilty of orchestrating a $7bn Ponzi scheme.

After a six-week trial in Houston, Texas, a jury found him guilty of conspiracy and 12 other criminal charges including obstruction. He was acquitted of one wire fraud charge.

Stanford, who turns 62 on 24 March, faces up to 20 years in prison when he is sentenced.

The jury of eight men and four women had appeared to be deadlocked on Monday and had to be given instructions by the judge, David Hittner. Outside, family members had gathered to offer their support.

"I'm hoping for the best," Stanford's 84-year-old father, James, told the Houston Chronicle as he waited for the verdict. "We support him 100%. In fact, 150%."

During the trial prosecutors argued that Stanford used his clients' money to fuel his "lavish lifestyle and his loser companies" in a massive Ponzi scheme that spanned two decades. Stanford, they argued, conned investors into buying certificates of deposit, or CDs, from his bank on the Caribbean island nation of Antigua, telling them they were a safe investment. Instead the bank was "his own personal ATM", the prosecutor William Stellmach said.

By 2008 Stanford's bank owed depositors more than $7bn that it did not have and Stanford had blown huge chunks of that cash on luxury yachts, private jets and cricket sponsorship.

In damning testimony James Davis, Stanford Financial Group's former chief financial officer, told jurors his boss was "the chief faker" – a man who threatened to fire anyone who questioned the $2bn prosecutors say he pocketed from his Antiguan bank.

The picture that emerged during Davis's testimony was one of a long spending spree to disaster. By the end of December 2008 Stanford International Bank had only $88m in cash, but claimed to hold $1bn in assets.

As worried investors pulled out their cash, Davis told the court Stanford tried to use his beloved Antigua to bail him out. He cooked the books and 1,500 undeveloped acres Stanford had bought on the island for $64m were set to be valued at $3.2bn, Davis told the court.

Stanford's attorneys argued that the bank would be solvent today if the US government had not shut it down in February 2009. They did not put the businessman on the witness stand, although Stanford had reportedly wanted to testify.